A study was carried out involving the filling of epoxy resin (EP) with bentonites and silica modified with polyhedral oligomeric silsesquioxane (POSS). The method of homogenization and the type of filler affect the functional and canceling properties of the composites was determined. The filler content ranged from 1.5% to 4.5% by mass. The basic mechanical properties of the hybrid composites were found to improve, and, in particular, there was an increase in tensile strength by 44%, and in Charpy impact strength by 93%. The developed hybrid composites had characteristics typical of polymer nanocomposites modified by clays, with a fine plate morphology of brittle fractures observed by SEM, absence of a plate separation peak in Wide Angles X-ray Scattering (WAXS) curves, and an exfoliated structure observed by TEM.

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In this article the research related to the scope increase of incremental technology in machine industry is presented. Those technologies were used for the manufacture of components from polymeric materials with torque loaded such as: shafts, clutches of gear hubs and other elements of the propulsion system in which torque is transferred. To analyze the properties of the manufactured elements the original testing stand was designed and a series of preliminary torsional strength tests of the gear shaft fittings obtained using additive techniques have been carried out. On the basis of the obtained results it was stated that there is a clear influence of the printing plane in the applied incremental technologies [SLS (selective laser sintering) and FFF (fused filament fabrication)] on the torsion resistance of the obtained elements. The properties of the shafts also depend on the type of polymeric materials which they were made of.

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An important factor having an impact on the condition of machine parts is their surface topography. For instance, in the production of a molded element in casting or injection molding processes, the surface topography of the molding cavity has a significant impact on the surface condition of the product. An analysis of the wear of a mold made with the PolyJet technique was performed in this work, and we examined the surface topography using the stylus method after casting a wax model of the turbine blade. The surface topographies showed a gradual degradation of the mold cavity surface. After the manufacture of 40 castings, there was a significant deformation of the microstructure of the mold cavity. The maximum height value (Sz) parameter had the most dynamic change from 18.980 to 27.920 μm. Its growth dynamics are mainly influenced by maximum peak height (Sp) rather than the maximum pit height (Sv) parameter. In the case of the root mean square height (Sq) and arithmetic mean height (Sa), their gradual increases can be seen from 2.578 to 3.599 μm and from 2.038 to 2.746 μm. In the case of the value of the skewness (Ssk) parameter, a small positive skew was observed. As for the kurtosis (Sku) values, the distributions are clearly leptokurtic.

Oceniano właściwości mechaniczne oraz przetwórcze kompozytów otrzymanych na osnowie żywicy epoksydowej (EP) i napełniaczy hybrydowych, zwłaszcza pod kątem ich zastosowania w metodach szybkiego prototypowania do wytwarzania modeli kół zębatych. Weryfikację dokładności odwzorowania kształtu geometrycznego modelu wykonano za pomocą bezstykowego systemu optycznego opartego na współrzędnościowym skanerze optycznym ATOS Triple Scan II Blue Light firmy GOM. Wytworzone kompozyty hybrydowe wykazywały znacznie lepsze właściwości mechaniczne niż nienapełniona żywica epoksydowa. Dzięki wprowadzeniu do osnowy EP hybrydowych napełniaczy uzyskano ograniczenie skurczu promieniowego i osiowego, co wpłynęło na radykalną poprawę dokładności odwzorcowania kształtu geometrycznego odlewanych kół zębatych. Słowa kluczowe: kompozyty polimerowe, skaner optyczny, dokładność geometryczna, modele kół zębatych, napełniacze. Application of ATOS II optical system in the techniques of rapid prototyping of epoxy resin-based gear models Abstract: The mechanical and processing properties of composites with epoxy resin (EP) matrix and hybrid fillers, especially with regard to their use in rapid prototyping methods for the preparation of gear models, were evaluated. The accuracy assessment of geometric model shape mapping was performed using a non-contact optical system based on the coordinate optical scanner ATOS Triple Scan II Blue Light from GOM company. The produced hybrid composites show much better mechanical properties than those of unfilled epoxy resin. By introducing the hybrid fillers into EP matrix, a reduction in radial and axial shrinkage was achieved, which led to a radical improvement in the accuracy of geometric shape mapping of gear castings.

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Kompozyty ¿ywicy epoksydowej zawieraj¹ce modyfikowane bentonity Streszczenie-Przedmiotem pracy by³a organofilizacja bentonitów czwartorzêdow¹ sol¹ amoniow¹-chlorkiem alkilo-benzylo-di-metyloamoniowym (QAS)-i zbadanie mo¿liwooeci zastosowania otrzymanego produktu jako nape³niacza ¿ywic epoksydowych (EP). Skutecznooeae takiej modyfikacji (stopieñ rozsuniêcia p³ytek w bentonicie) oceniano metod¹ rentgenograficzn¹. P³ynne kompozycje EP ze zmodyfikowanymi bentonitami charakteryzowa³y siê du¿ym wspó³czynnikiem tiksotropii, a dal-sz¹ ich zalet¹ by³o ograniczenie sedymentacji dodatku podczas przechowywania mieszaniny. Stwierdzono, ¿e dodatek modyfikowanych bentonitów (w ilooeci ≤5,0 % mas.) do handlowej ¿ywicy epoksydowej spowodowa³ znaczn¹ poprawê wytrzyma³ooeci na rozci¹ganie, wyd³u¿enia wzglêdnego przy zerwaniu, twardooeci wg Brinella i zw³aszcza udarnooeci bez karbu (niekiedy niemal trzykrotn¹). Zaobserwowano przy tym wyraŸny wp³yw temperatury homogenizacji ¿ywicy z nape³niaczem na zbadane w³aoeciwooeci mechaniczne kompozytów. Kompozyty EP z modyfikowanymi bentonitami wykazy-wa³y cechy nanokompozytów: zwiêkszon¹ sztywnooeae, wytrzyma³ooeae, przezroczystooeae i scharaktery-zowan¹ metod¹ skaningowej mikroskopii elektronowej drobnop³ytkow¹ morfologiê prze³omu. S³owa kluczowe: ¿ywice epoksydowe, bentonity, organofilizacja, kompozyty, tiksotropia, w³aoeciwooeci mechaniczne, morfologia. EPOXY RESIN COMPOSITES CONTAINING MODIFIED BENTONITES Summary-The subject of the paper is organophilization of bentonites (Table 1) with quaternary ammonium salt (QAS): alkylbenzyldimethylammonium chloride, and investigation of the product application as a filler for epoxy resins (EP). The effectiveness of such modification of a clay (degree of bentonite platelets' intercalation) was evaluated using X-ray diffraction method (Fig. 2). Liquid EP compositions with modified bentonites showed high thixotropy coefficient. Limited sedimentation of the filler during the storage was the additional advantage of them (Fig. 3, Table 2). It was found that the addition of modified bentonite (in an amount up to 5.0 wt. %) to the commercial epoxy resin caused significant improvement in tensile strength, unit elongation at break, Brinell hardness and especially unnotched impact strength (sometimes even threefold). A clear effect of homogenization temperature of the resin filled on the tested mechanical properties of the composites was also observed (Table 3-6, Fig. 4-11). The composites of EP with modified bentonites showed the features of nanocomposites: improved stiffness, strength, transparency and fine-platelets morphology of fractures, characterized by scanning electron microscopy (Fig. 12-15).